Portion of a watch



FIG. 1 is a perspective view of a portion of a watch showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof, the bottom view being a mirror image thereof; and,

FIG. 4 is a right side view thereof, the left side view being a mirror image thereof.

The broken line showing of the inside of the watch, the side buttons, and the remainder of the watch band is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a portion of a watch, as shown and described. 